It goes without saying that Las Vegas is a destination wedding town - most of our clients are coming from all over the country and world and even planning some extravagant affairs. A common statement is that they want their guests to have fun and enjoy their time here since it is also a vacation. Common questions we get are "what should we put in our Las Vegas themed welcome bags?". Here are some of my ideas:

A nice welcome note handwritten by you
Since your guests will likely be here for a few days, it would be nice to put an itinerary in the welcome bags (it may be redundant if this is already on your wedding website but hopefully people will not be too connected while away on vacation!)
Lotion - It's an extremely dry climate here
Eye drops - Again, it's very dry here and your guests will be thankful
Poker chip - yes, a real one
Sunscreen
Sunglassses
Chapstick
If you're hired a local wedding planner, ask her for some restaurant, show, and activity suggestions
Aspirin
Mints
Mini fan
Starbucks gift card
Bottles of water to ensure they stay hydrated
A few small bags of snacks
Shot glass souvenir
Splits of Champagne, sparkling wine, and/or apple cider
If feasible, a custom designed map by Laura Hooper is a nice added touch: